January 2012 Capital Investment - National Grid

Exhibit ___ (EIOP-19)Page 12 of 684Distribution System SummaryThe Company’s distribution system comprises lines and substations typically operatingat 15kV and below. There are nearly 36,000 miles of overhead primary wire and nearly7,500 miles of underground primary cable on the system supplying approximately412,774 overhead, padmount and underground transformers. Additionally, there arealmost 424 substations providing service to the Company’s 1.6 million electriccustomers. 3 The current five year plan for distribution is represented in Table I-6.Table I-6Distribution System Capital Expenditure by Spending Rationale ($millions)Rationale FY13 FY14 FY15 FY16 FY17 TotalStatutory orRegulatory141.1 137.6 135.1 139.8 143.3 697.0Damage/Failure 25.9 26.1 26.4 26.7 27.5 132.6System Capacityand Performance43.1 52.1 53.4 55.3 56.2 260.1Asset Condition 29.2 34.5 44.3 47.8 49.8 205.7Non-Infrastructure4.7 4.7 5.8 5.3 5.1 25.7Total 244.0 255.0 265.0 275.0 282.0 1,321.0This Plan envisions the majority of investment in the distribution system will be in theStatutory or Regulatory Requirements spending rationale.Figure I-5Distribution System Mandatory InvestmentDistribution Capital By Spending Rationale(Mandatory Work Solid Color)Statutory orRegulatory52%Non-Infrastructure2%System Capacity andPerformance20%Damage/Failure10%Asset Condition16%3 The distribution system data was taken December 6, 2011 from National Grid Asset InformationWebsite located at http://usinfonet/sites/asset_info/Pages/AssetStatistics.aspx.I-1013